GPT-5.6 Luna is the fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume chat, classification, lightweight agentic workflows, and latency-sensitive reasoning tasks.
Added Jul 9, 2026
Context Window
1.1M
Max Output
128.0K
Input Price (Auto)
$0.10/1M
Output Price (Auto)
$0.60/1M
Cache Read (Auto)
$0.0100/1M
Capabilities
Benchmarks
Benchmarks
Performance metrics and benchmarks
Sourced from Design Arena.
Best Category
UI Component
Best Elo
1278
Best Rank Percentile
Top 21%
Ranking Distribution
10,614 battles
60%
45%
30%
15%
0%
11.4%
First
35.8%
Second
38.5%
Third
14.3%
Fourth
Category Performance
Models Arena
UI Component
1278
Elo
50.4%
Win
34.7s
Avg Time
#31
Rank
Website
1268
Elo
50.9%
Win
41.9s
Avg Time
#34
Rank
SVG
1242
Elo
52.9%
Win
15.9s
Avg Time
#24
Rank
Data Visualization
1239
Elo
48.0%
Win
33.4s
Avg Time
#43
Rank
Game Development
1233
Elo
44.4%
Win
33.4s
Avg Time
#48
Rank
ASCII Art
1199
Elo
46.6%
Win
14.3s
Avg Time
#28
Rank
3D
1176
Elo
38.9%
Win
29.4s
Avg Time
#74
Rank
Updated Aug 25, 2026, 10:08 AM · Matched as GPT 5.6 Luna
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Related text models
Compare GPT 5.6 Luna with similar models from the same provider or model family.
GPT 5.6 Luna Pro
openai/gpt-5.6-luna-proGPT-5.6 Luna with Pro reasoning mode. Pro mode performs more model work for difficult tasks; reasoning effort remains independently configurable and defaults to medium.
GPT 5.6 Sol
openai/gpt-5.6-solGPT-5.6 Sol is the flagship model in OpenAI's GPT-5.6 series. It is suited for complex reasoning, coding, agentic workflows, command-line work, and multi-step professional tasks.
GPT 5.6 Sol Pro
openai/gpt-5.6-sol-proGPT-5.6 Sol with Pro reasoning mode. Pro mode performs more model work for difficult tasks; reasoning effort remains independently configurable and defaults to medium.
GPT 5.6 Terra
openai/gpt-5.6-terraGPT-5.6 Terra is the balanced model in OpenAI's GPT-5.6 series, positioned between flagship Sol and cost-efficient Luna. It is suited for everyday coding, reasoning, agentic work, and general professional tasks.
GPT 5.6 Terra Pro
openai/gpt-5.6-terra-proGPT-5.6 Terra with Pro reasoning mode. Pro mode performs more model work for difficult tasks; reasoning effort remains independently configurable and defaults to medium.
GPT Chat Latest
openai/gpt-chat-latestCompatibility chat alias that routes to GPT 5.6 Sol, the flagship GPT-5.6 tier for complex reasoning, coding, and agentic workflows.